Biomaterial Database

Altered hypothalamic-pituitary function in the adult female rat with streptozotocin-induced diabetes. 1985

M Spindler-Vomachka, and D C Johnson

Infertility associated with anovulation and loss of regular oestrous cyclicity is a consequence of diabetes mellitus in the rat. In an attempt to define loci of altered function, studies were undertaken to examine various aspects of hypothalamic-pituitary function in rats treated with streptozotocin. Medial basal hypothalamic fragments from adult female diabetic rats contained the same amount of gonadotrophin-releasing hormone but, with depolarization, released slightly but insignificantly (p greater than 0.05) more than did those from control animals. Furthermore, release of luteinizing hormone from pituitaries exposed to hypothalamic gonadotrophin-releasing hormone was not altered by diabetes. Removal of the negative feedback effect of gonadal steroids upon the hypothalamic-pituitary axis produced an increase in luteinizing hormone and follicle stimulating hormone concentrations in the serum of normal rats within 6h (p less than 0.05), whereas 24h were required for similar increases in diabetic rats. However, the same concentrations of gonadotrophins were found in diabetic and control animals 120 h after ovariectomy. The inhibitory action of oestradiol benzoate on the secretion of gonadotrophins was more pronounced in ovariectomized diabetic than in control rats. A 74% depression in serum luteinizing hormone (p less than 0.01) was produced by 0.5 microgram oestradiol benzoate per day in diabetic rats, while 5 micrograms was required in control animals. Similar reductions in follicle stimulating hormone concentrations (50%, p less than 0.05) were obtained by injecting 5 micrograms of the oestrogen into diabetic or 50 micrograms into control rats. Increases in serum prolactin were greater in the control animals however.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007030	Hypothalamo-Hypophyseal System	A collection of NEURONS, tracts of NERVE FIBERS, endocrine tissue, and blood vessels in the HYPOTHALAMUS and the PITUITARY GLAND. This hypothalamo-hypophyseal portal circulation provides the mechanism for hypothalamic neuroendocrine (HYPOTHALAMIC HORMONES) regulation of pituitary function and the release of various PITUITARY HORMONES into the systemic circulation to maintain HOMEOSTASIS.	Hypothalamic Hypophyseal System,Hypothalamo-Pituitary-Adrenal Axis,Hypophyseal Portal System,Hypothalamic-Pituitary Unit,Hypothalamic Hypophyseal Systems,Hypothalamic Pituitary Unit,Hypothalamo Hypophyseal System,Hypothalamo Pituitary Adrenal Axis,Portal System, Hypophyseal
D007031	Hypothalamus	Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE.	Lamina Terminalis,Preoptico-Hypothalamic Area,Area, Preoptico-Hypothalamic,Areas, Preoptico-Hypothalamic,Preoptico Hypothalamic Area,Preoptico-Hypothalamic Areas
D007986	Luteinizing Hormone	A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.	ICSH (Interstitial Cell Stimulating Hormone),Interstitial Cell-Stimulating Hormone,LH (Luteinizing Hormone),Lutropin,Luteoziman,Luteozyman,Hormone, Interstitial Cell-Stimulating,Hormone, Luteinizing,Interstitial Cell Stimulating Hormone
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D010903	Pituitary Gland, Anterior	The anterior glandular lobe of the pituitary gland, also known as the adenohypophysis. It secretes the ADENOHYPOPHYSEAL HORMONES that regulate vital functions such as GROWTH; METABOLISM; and REPRODUCTION.	Adenohypophysis,Anterior Lobe of Pituitary,Anterior Pituitary Gland,Lobus Anterior,Pars Distalis of Pituitary,Adenohypophyses,Anterior Pituitary Glands,Anterior, Lobus,Anteriors, Lobus,Lobus Anteriors,Pituitary Anterior Lobe,Pituitary Glands, Anterior,Pituitary Pars Distalis
D010906	Pituitary Hormone-Releasing Hormones	Peptides, natural or synthetic, that stimulate the release of PITUITARY HORMONES. They were first isolated from the extracts of the HYPOTHALAMUS; MEDIAN EMINENCE; PITUITARY STALK; and NEUROHYPOPHYSIS. In addition, some hypophysiotropic hormones control pituitary cell differentiation, cell proliferation, and hormone synthesis. Some can act on more than one pituitary hormone.	Hormones, Pituitary Hormone Releasing,Hypophysiotropic Hormones,Hypothalamic Hypophysiotropic Hormone,Hypothalamic Releasing Factor,Hypothalamic Releasing Hormone,Hypothalamic Releasing Hormones,Hormone, Hypothalamic Hypophysiotropic,Hormones, Hypophysiotropic,Hypophysiotropic Hormone, Hypothalamic,Pituitary Hormone Releasing Hormones,Releasing Hormone, Hypothalamic
D011388	Prolactin	A lactogenic hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). It is a polypeptide of approximately 23 kD. Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation. Prolactin receptors are present in the mammary gland, hypothalamus, liver, ovary, testis, and prostate.	Lactogenic Hormone, Pituitary,Mammotropic Hormone, Pituitary,Mammotropin,PRL (Prolactin),Hormone, Pituitary Lactogenic,Hormone, Pituitary Mammotropic,Pituitary Lactogenic Hormone,Pituitary Mammotropic Hormone
D002369	Castration	Surgical removal or artificial destruction of gonads.	Gonadectomy,Castrations,Gonadectomies
D003921	Diabetes Mellitus, Experimental	Diabetes mellitus induced experimentally by administration of various diabetogenic agents or by PANCREATECTOMY.	Alloxan Diabetes,Streptozocin Diabetes,Streptozotocin Diabetes,Experimental Diabetes Mellitus,Diabete, Streptozocin,Diabetes, Alloxan,Diabetes, Streptozocin,Diabetes, Streptozotocin,Streptozocin Diabete
D004958	Estradiol	The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.	17 beta-Estradiol,Estradiol-17 beta,Oestradiol,17 beta-Oestradiol,Aerodiol,Delestrogen,Estrace,Estraderm TTS,Estradiol Anhydrous,Estradiol Hemihydrate,Estradiol Hemihydrate, (17 alpha)-Isomer,Estradiol Monohydrate,Estradiol Valerate,Estradiol Valeriante,Estradiol, (+-)-Isomer,Estradiol, (-)-Isomer,Estradiol, (16 alpha,17 alpha)-Isomer,Estradiol, (16 alpha,17 beta)-Isomer,Estradiol, (17-alpha)-Isomer,Estradiol, (8 alpha,17 beta)-(+-)-Isomer,Estradiol, (8 alpha,17 beta)-Isomer,Estradiol, (9 beta,17 alpha)-Isomer,Estradiol, (9 beta,17 beta)-Isomer,Estradiol, Monosodium Salt,Estradiol, Sodium Salt,Estradiol-17 alpha,Estradiol-17beta,Ovocyclin,Progynon-Depot,Progynova,Vivelle,17 beta Estradiol,17 beta Oestradiol,Estradiol 17 alpha,Estradiol 17 beta,Estradiol 17beta,Progynon Depot